Many surgical procedures involve the use of energy-based surgical instruments such as electrosurgical blades, probes, scissors, graspers, dissectors, electrocautery instruments and the like. Generally, electrosurgery is performed using an electrosurgical generator connected to an alternating current power supply and an instrument including one or more electrodes. Voltage is provided by the generator and high-frequency electric current typically in the range of 200 kHz to 3.3 MHz is delivered to biological tissue through the electrode tip of the instrument or handpiece as a means to cut, coagulate, desiccate or fulgurate tissue. As the current is delivered, it passes through and heats the tissues to create the desired clinical effect. Alternatively, the electrical current is used to heat an instrument and a clinical effect is realized when the heated instrument is applied to tissue as in electrocautery. Additionally, many procedures make use of energy devices based on high frequency sound also known as ultrasound devices. These and other energy-based instruments advantageously provide a surgeon with the ability to make precise and nearly effortless cuts, dissect tissue and nearly instant thermal hemostasis limiting blood loss. Such instruments have become a standard within the surgical community and are used regularly in a variety of procedures.
Because of the effectiveness of electrosurgical and other energy-based instruments and procedures, it is important to train the clinician in the use of energy-based surgical instruments and procedures. Many of the existing training or simulating modules use live tissue from animals or cadavers. Real live tissue may be expensive and difficult to obtain, requires preservation using refrigeration and generates a smoke plume and odor when cauterized. With real tissue, a grounding plate is attached to an electrosurgical generator and the grounding plate is placed underneath the patient so that the current penetrates deeper into the tissues. In general, the practice of electrosurgical techniques using real tissue requires additional safety considerations. Alternatively, in some simulation modules, synthetic materials that mimic the characteristics of living tissue are also employed in place of real tissue. Some of these synthetic materials that mimic the look and feel of real tissue include silicone elastomers, natural latex, polyurethane elastomers and styrenic-block copolymers. In order to serve as simulated tissue for practicing the use of energy-based surgical instruments, synthetic organ models must be wetted or infused with saline solution or embedded with materials such as metallic particles so that they are electrically conductive. Generally, the elastomeric materials are dielectric unless specially treated to conduct electric current. However, the most preferred synthetic materials such as silicone rubber, latex, vinyl, polyester, polyurethane and the like do not respond to energy-based surgical devices in a way that satisfies the need to train users to use the devices in an actual surgical procedure. Hence, there is a need to provide a system and method for simulating energy-based instruments that employs non-living, non-electrically conductive simulation tissue, yet simulates electrically conductive, living tissue for the practice of techniques used in electrosurgery, electrocautery and other energy-based systems. In order to simplify training and minimize the use of cadavers in surgical training, the present invention uses synthetic, materials that are compounded, configured and combined to emulate the properties, responses and characteristics of human or animal tissue under surgical conditions and in response to the activities of energy-based instruments. Such conditions and activities may include incision, penetration, dissection, occlusion, anastamosis, approximation, ablation, and the like.